How to repair old marble stone

1. Inspect The Marble For Damage

Before making any adjustments or modifying the appearance of a marble surface, first, inspect your marble surface in detail for:
Find any small cracks – these would be small shallow lines that run along the surface
Large cracks – there would be some deep penetrations into the marble needing repair from below
Missing pieces of marble/chips – this occurs commonly on corners & edges
Stains; will generally occur from acid-based products used to create or clean surfaces
Dirt/dullness – surfaces that have been worn by everyday use will show dullness

Once you have inspected thoroughly for damage, it is easy for you to choose what way to repair your marble.

2. Properly Clean The Surface Of Your Marble

Proper cleaning will enable for better adhesion of repairs, therefore producing a smoother finished.product
Cleaning marble correctly includes:
Using only ph neutral cleaners that are safe for natural stones & non-acidics
Using only warm soapy water with a pH neutral cleaner
Gently scrub with a cloth or sponge while avoiding any abrasive material (ie: steel wool, Scotchbrite pads, etc.)
Do not use any acid products (vinegar or lemon juice)—to clean marble.
Make sure you allow the surface of the marble to be thoroughly dried before any type of repairs.
3. Repair Any Cracked Marble With High Quality Marble Epoxy

The best method for repairing cracks in your marble is with high-quality marbles epoxies or stone adhesives.
What does that entail?When doing repairs to your marble there is a process to follow in order to complete it successfully.
1. Select an appropriate dye or pigment to color your epoxy (if coloring).
2. Use a putty knife or spatula to fill in the crack.
3. Fill slightly higher than the surface of the cracked area to allow room for sanding smooth.
4. Follow the manufacturer’s recommendation as to the drying/curing time (often 24 hours).
5. For fine cracks, i.e. hairline, you may use a more runny or low viscosity epoxy to provide greater penetration into the crack.
6. If you have chipped or missing pieces of marble, the process is detailed below.
1. Wash the area that has missing/chipped material (clean).
2. Select a knife-grade epoxy (more viscous) for repair.
3. Apply epoxy to chip area, smooth to original shape.
4. Let the epoxy cure completely before proceeding.
5. Sand edges of chip repair to level with the surface.
6a. If you have your original piece, you can glue it back to the base with a structural adhesive for stone, otherwise, you can fill the void left by the loss of the original piece with a colored marble epoxy.
7. After the repairs have cured (12-24 hours) you are ready to begin sanding the surface smooth.
1. Use 400-grit sandpaper to start sanding process.Increase the grit gradually to a finer grit from 800 to 1500.
You may want to keep the surface damp while sanding so that you do not create any dust and scratch the surface of the marble.
By using this method of grinding and blending the new repair with the existing marble surface, the repairs can be blended in with the other areas in the marble.

Now to restore the existing polish back to the marble finish.
The marble has been polished to give it that natural shine that most people love to have in their homes.
To achieve that polished look, there are several steps to follow:
Use a marble polishing powder or paste.
Polish with either a soft cloth or a polishing pad.
When polishing with a circular motion.
Continue polishing until you have achieved your desired level of polished finish.
If you are polishing an area that is large enough then it is a good idea to use a low-speed polisher.
Finally seal the marble surface.

Sealing your marble will help to safeguard your marble from being damaged in the future.
Start off with a penetrating marble sealer.
Let the marble sit to absorb the sealer.
After waiting the time recommends wipe off all excess sealer and let the marble cure.
Sealing your marble will help to limit the damage from staining and extend the life of repairs made.
To keep your old marble looking good and well maintained be sure to do the following:
Make sure to wipe up spills immediately after they occur.
Use coasters or mats to avoid etching your marble.
Do not use any harsh or acidic cleaning products on your marble.
Re-seal your marble surface every 6 to 12 months.

Final Thoughts
Restoration of old marble stone is possible and can be done if you put forth the necessary time and effort. Following each step of cleaning the marble correctly, using the correct type of epoxy for the repair, sanding it appropriately, polishing and sealing the marble will all contribute to making your marble look as close to its original condition as possible. Whether it be a minor hairline crack or large chip all repairs require a close attention to detail and a level of commitment. If you are dealing with significant amounts of damage or structural issues with the stone, consider contacting a professional stone restoration contractor to assist you in achieving the best possible results with the restoration of your old marble stone.